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	<meta http-equiv="Content-Type" content="text/html;charset=UTF-8">
	<title>Document</title>
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<body>
	<script type="text/javascript">
		// var a = "1";   	//字符串
		// var b = 2;		//数字
		// console.log(a + b);


		// var a = 1;		//数字
		// var b = 2;		//数字
		// console.log(a + b);


		// var a = 1;
		// var b = 2;
		// console.log("a" + b);	//"a"就不是变量了！所以就是"a"+2 输出a2


		// var a = 234234;
		// var b = 234323112;
		// console.log("a+b");			//由于加上了引号，所以就表示原样输出


		var a = 123;
		var b = "123";
		console.log(a + "b");
	</script>
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